A display panel having a touch function is widely used in display devices such as cellphones, tablet computers, public information inquiry machines and the like. A user can operate the display device with a finger by only touching a logo on the display panel, which eliminates the user's dependence on other input devices (such as keyboards and mice), thereby making human-computer interaction easier.
In order to meet the user's requirements better, a force sensor is usually provided in the display panel for detecting the force subjected by the display panel from the user, so as to enable the display panel not only to collect touch position information, but also to collect force magnitude information, thereby enlarging the application range of touch technologies.
The structure of the display panel is complex and includes a plurality of film layers. When an external force is applied, the layers may be elastically deformed or non-elastically deformed, in which the non-elastic deformation remains in the layers and the layers cannot be restored from the non-elastic deformation, so that stress is accumulated in the display panel. Therefore, the force sensor still has a certain deformation even though the position where the force sensor is located is not subjected to force, thereby leading to baseline drifting of the force sensor, which may influence the detection accuracy of the force sensor with respect to the force.